initial screening of environmentally sustainable surface ... screening of environmentally...

ARL-TR-8014 ● MAY 2017

US Army Research Laboratory

Initial Screening of Environmentally Sustainable Surface Pretreatments for Adhesive Bonding Applications by Miriam S Silton, David P Flanagan, Daniel C DeSchepper, and Robert E Jensen

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NOTICES

Disclaimers

The findings in this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an official endorsement or approval of the use thereof. Destroy this report when it is no longer needed. Do not return it to the originator.

ARL-TR-8014 ● MAY 2017

US Army Research Laboratory

Initial Screening of Environmentally Sustainable Surface Pretreatments for Adhesive Bonding Applications by Miriam S Silton The Academy of Applied Science via the Qualified Leaders Program, Aberdeen Proving Ground, MD David P Flanagan, Daniel C DeSchepper, and Robert E Jensen Weapons and Materials Research Directorate (ARL) Approved for public release; distribution is unlimited.

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1. REPORT DATE (DD-MM-YYYY)

May 2017 2. REPORT TYPE

Technical Report 3. DATES COVERED (From - To)

June 2015–January 2017 4. TITLE AND SUBTITLE

Initial Screening of Environmentally Sustainable Surface Pretreatments for Adhesive Bonding Applications

5a. CONTRACT NUMBER

W911SR-15-2-0001 5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)

Miriam S Silton, David P Flanagan, Daniel C DeSchepper, and Robert E Jensen

5d. PROJECT NUMBER

R.0010455.2.92 5e. TASK NUMBER

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

US Army Research Laboratory ATTN: RDRL-WMM-C Aberdeen Proving Ground MD 21005-5069

8. PERFORMING ORGANIZATION REPORT NUMBER

ARL-TR-8014

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

10. SPONSOR/MONITOR'S ACRONYM(S)

11. SPONSOR/MONITOR'S REPORT NUMBER(S)

12. DISTRIBUTION/AVAILABILITY STATEMENT


13. SUPPLEMENTARY NOTES

14. ABSTRACT

A methacrylate adhesive marketed for high-temperature applications was screened in combination with environmentally sustainable TT-C-490F surface pretreatments. Testing consisted of single-lap-joint testing using aluminum and steel specimens at room temperature along with hot/wet (H/W) conditioning (water immersion for 14 d at 63 °C) and in-situ at elevated temperature (ET) (71 °C). The methacrylate adhesive showed high initial bond strength and H/W durability but significant loss of strength retention at ET. The environmentally sustainable TT-C-490F Type IV inorganic pretreatments resulted in little to no loss of adhesive bond strength during H/W conditioning and their potential use as bonding pretreatments is worth further investigation.

15. SUBJECT TERMS

methacrylate adhesive, single-lap-joint, TT-C-490F, wash primer, pretreatment

16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT

UU

18. NUMBER OF PAGES

76

19a. NAME OF RESPONSIBLE PERSON

Robert E Jensen a. REPORT

Unclassified b. ABSTRACT

Unclassified

c. THIS PAGE

Unclassified

19b. TELEPHONE NUMBER (Include area code)

410-306-1910 Standard Form 298 (Rev. 8/98)

Prescribed by ANSI Std. Z39.18

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Contents

List of Figures v

List of Tables xi

Acknowledgments xii

1. Introduction 1

2. Experimental 2

2.1 Materials and Environmental Assessment 2

2.2 Joint Geometry 3

2.2.1 Surface Preparation 4

2.2.2 Bonding 5

2.3 Testing 6

2.3.1 Mechanical Testing 6

2.3.2 Dynamic Mechanical Analysis 7

3. Results 8

4. Discussion 11

5. Conclusions 17

6. References 18

Appendix A. Environmental Restrictions Listed against the Adhesive and Surface Pretreatments 21

Appendix B. Load versus Displacement Curves and Failure Surface Scans 25

Appendix C. Supporting Digital File Archive Index 57

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List of Symbols, Abbreviations, and Acronyms 59

Distribution List 61

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List of Figures

Fig. 1 Notional life-cycle costs for a DOD weapon system ............................ 1

Fig. 2 Illustration of the adhesively bonded single-lap-joint test specimen configuration (refer to ASTM D1002-10 for dimensions) ................... 3

Fig. 3 Single-lap-joint coupons undergoing dip-coat pretreatment................. 4

Fig. 4 Single-lap-joint bonding tooling fixture components ........................... 5

Fig. 5 Stacking assembly for fabrication of single-lap-joint panel ................. 6

Fig. 6 Average maximum strength at failure (MPa) for aluminum 2024 T3, RT, H/W, and ET conditioning ............................................................. 9

Fig. 7 Average maximum displacement at failure (mm) for aluminum 2024 T3, RT, H/W, and ET conditioning ........................................... 10

Fig. 8 Average maximum strength at failure (MPa) for 1010 mild steel, RT, and H/W conditioning. ET conditioning not tested for steel samples. ............................................................................................... 10

Fig. 9 Average maximum displacement at failure (mm) for 1010 mild steel, RT, and H/W conditioning. ET conditioning not tested for steel samples. ............................................................................................... 11

Fig. 10 Load vs. displacement response for aluminum single-lap-joints pretreated by grit blasting and with ZIRCOBOND TT-C-490F Type IV surface pretreatment....................................................................... 12

Fig. 11 Failure surfaces for aluminum single-lap-joint with grit-blasted surface (left) and ZIRCOBOND 4200 (right) pretreatments .......................... 12

Fig. 12 Load vs. displacement response for aluminum single-lap-joints pretreated with APS, steel samples pretreated with AC-131, and steel and aluminum pretreated with ZIRCOBOND TT-C-490F Type IV surface pretreatment ............................................................................ 13

Fig. 13 Failure surfaces for aluminum single-lap-joint pretreated with APS (left) and steel pretreated with AC-131 (right) ................................... 14

Fig. 14 Load vs. displacement response for grit-blasted aluminum single-lap-joints tested at RT and 71 °C .............................................................. 16

Fig. 15 Failure surfaces for grit-blasted aluminum single-lap-joints tested at RT (left) and 71°C (right) ................................................................... 16

Fig. 16 Storage modulus (E’) and loss modulus (E’’) vs. temperature for SG805 ................................................................................................. 17

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Fig. B-1 Load vs. extension (displacement) for single-lap-joints with aluminum oxide grit blast surface pretreatment. Materials Selection and Analysis Tool (MSAT) identifications (IDs) = 20150215–20150219, substrate = 2024 T3 aluminum, sample conditioning = RT. ............................. 26

Fig. B-2 Failure surfaces for single-lap-joint with aluminum oxide grit blast surface pretreatment. MSAT ID = 20150215, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = mixed-mode (MM). ........................................................................................ 26

Fig. B-3 Load vs. extension (displacement) for single-lap-joints with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT IDs = 20150225–20150229, substrate = 2024 T3 aluminum, and sample conditioning = RT. .............................................................................. 27

Fig. B-4 Failure surfaces for single-lap-joint with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT ID = 20150225, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive. ..................................................... 27

Fig. B-5 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150235–20150239, substrate = 2024 T3 aluminum, and sample conditioning = RT. ....................... 28

Fig. B-6 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150235, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = MM. .................... 28

Fig. B-7 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150245–20150249, substrate = 2024 T3 aluminum, and sample conditioning = RT. ........ 29

Fig. B-8 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150245, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = MM. .................... 29

Fig. B-9 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150255–20150259, substrate = 2024 T3 aluminum, and sample conditioning = RT. ........ 30

Fig. B-10 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150255, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive/ MM. .................................................................................... 30

Fig. B-11 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150265–20150269, substrate = 2024 T3 aluminum, and sample conditioning = RT. ........ 31

Fig. B-12 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150265, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive/ MM. .................................................................................... 31

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Fig. B-13 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150275–20150279, substrate = 2024 T3 aluminum, and sample conditioning = RT. ................................................................................................... 32

Fig. B-14 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150275, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive/ MM. .................................................................................... 32

Fig. B-15 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150285–20150289, substrate = 2024 T3 aluminum, and sample conditioning = RT. ................................................................................................... 33

Fig. B-16 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150285, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = MM. .................... 33

Fig. B-17 Load vs. extension (displacement) for single-lap-joints with aluminum oxide grit blast surface pretreatment. MSAT IDs = 20150220–20150224, substrate = 2024 T3 aluminum, and sample conditioning = H/W. .................................................................................................... 34

Fig. B-18 Failure surfaces for single-lap-joint with aluminum oxide grit blast surface pretreatment. MSAT ID = 20150222, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM. 34

Fig. B-19 Load vs. extension (displacement) for single-lap-joints with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT IDs = 20150230–20150234, substrate = 2024 T3 aluminum, and sample conditioning = H/W. ........................................................................... 35

Fig. B-20 Failure surfaces for single-lap-joint with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT ID = 20150230, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive. ...................................................... 35

Fig. B-21 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150240–20150244, substrate = 2024 T3 aluminum, and sample conditioning = H/W. .................... 36

Fig. B-22 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150240, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM. ................. 36

Fig. B-23 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150250–20150254, substrate = 2024 T3 aluminum, and sample conditioning = H/W. ..... 37

Fig. B-24 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150250, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM. ................. 37

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Fig. B-25 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150260–20150264, substrate = 2024 T3 aluminum, and sample conditioning = H/W. ..... 38

Fig. B-26 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150260, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive/ MM. .................................................................................... 38

Fig. B-27 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150270–20150274, substrate = 2024 T3 aluminum, and sample conditioning = H/W. ..... 39

Fig. B-28 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150270, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive/ MM. .................................................................................... 39

Fig. B-29 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150280–20150284, substrate = 2024 T3 aluminum, and sample conditioning = H/W. .................................................................................................... 40

Fig. B-30 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150280, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive/ MM. .................................................................................... 40

Fig. B-31 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150290–20150294, substrate = 2024 T3 aluminum, and sample conditioning = H/W. ................................................................................................ 41

Fig. B-32 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150290, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM. ................. 41

Fig. B-33 Load vs. extension (displacement) for single-lap-joints with aluminum oxide grit blast surface pretreatment. MSAT IDs = 20150871–20150875, substrate = 2024 T3 aluminum, and test conditions = ET. 42

Fig. B-34 Failure surfaces for single-lap-joint with aluminum oxide grit blast surface pretreatment. MSAT ID = 20150871, substrate = 2024 T3 aluminum, and test conditions = ET. Mode-of-failure = MM. ........... 42

Fig. B-35 Load vs. extension (displacement) for single-lap-joints with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT IDs = 20150388–20150392, substrate = 2024 T3 aluminum, and test conditions = ET. .................................................................................. 43

Fig. B-36 Failure surfaces for single-lap-joint with 3-aminopropyltrimethoxysilane pretreatment. MSAT ID = 20150388, substrate = 2024 T3 aluminum, and test conditions = ET Mode-of-failure = adhesive. ............................................................................... 43

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Fig. B-37 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150438–20150442, substrate = 1010 steel, and sample conditioning = RT. ..................................... 44

Fig. B-38 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150438, substrate = 1010 steel, sample conditioning = RT. Mode-of-failure = MM. ....................................... 44

Fig. B-39 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150448–20150452, substrate = 1010 steel, and sample conditioning = RT. ...................... 45

Fig. B-40 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150448, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM. .......................... 45

Fig. B-41 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150458–20150462, substrate = 1010 steel, sample conditioning = RT. ............................. 46

Fig. B-42 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150461, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM. .................... 46

Fig. B-43 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150468–20150472, substrate = 1010 steel, and sample conditioning = RT. ...................... 47

Fig. B-44 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150468, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM. .................... 47

Fig. B-45 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150478–20150482, substrate = 1010 steel, and sample conditioning = RT. .... 48

Fig. B-46 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150478, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM. .................... 48

Fig. B-47 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150488–20150492, substrate = 1010 steel, and sample conditioning = RT. .... 49

Fig. B-48 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150492, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM. .......................... 49

Fig. B-49 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150443–20150447, substrate = 1010 steel, and sample conditioning = H/W. ................................... 50

Fig. B-50 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150443, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM. ........................ 50

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Fig. B-51 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150453–20150457, substrate = 1010 steel, and sample conditioning = H/W. ................... 51

Fig. B-52 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150453, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM. ........................ 51

Fig. B-53 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150463–20150467, substrate = 1010 steel, and sample conditioning = H/W. ................... 52

Fig. B-54 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150464, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM. ................. 52

Fig. B-55 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150473–20150477, substrate = 1010 steel, and sample conditioning = H/W. ................... 53

Fig. B-56 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150473, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM. ................. 53

Fig. B-57 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150483–20150487, substrate = 1010 steel, and sample conditioning = H/W. . 54

Fig. B-58 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150485, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM. ................. 54

Fig. B-59 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150493–20150497, substrate = 1010 steel, and sample conditioning = H/W. . 55

Fig. B-60 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150496, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM. ........................ 55

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List of Tables

Table 1 Aluminum 2024 T3, RT, H/W, and ET conditioning. Mode-of-failure: adhesive (ADH), cohesive (COH), and MM. ....................................... 8

Table 2 1010 mild steel, RT and H/W conditioning. ET conditioning not tested for steel samples. Mode-of-failure: ADH, COH, and MM. .................. 9

Table 3 Average property changes after H/W and ET conditioning ................ 15 Table C-1 Supporting data collection .................................................................. 58

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Acknowledgments

This research was supported in part by the US Army Education Outreach – Science and Engineering Apprentice Program - College Qualified Leaders Program at the US Army Research Laboratory and was administered by Academy of Applied Science (under contract number W911SR-15-2-0001). Mr John Kelley and Mr Charles Pergantis are acknowledged for their insightful technical reviews.

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1. Introduction

The greatest costs during the life-cycle of a Department of Defense (DOD) weapon system are those incurred in the operations and support phase, as shown in Fig. 1.1 (Note: Figure 1 is illustrative versus quantitative. Adapted from “Operating and Support Cost-Estimating Guide”. Published by the Office of the Secretary of Defense, Cost Analysis Improvement Group, 1992.) With regards to adhesively bonded assemblies, these operating expenses generally result from failures in the field due to inferior pretreatments, the adhesive’s inability to withstand elevated temperature (ET), and/or moisture exposure conditions. Additionally, as environmental regulations force various chemicals from the commercial market, the pretreatments and adhesives containing regulatory banned constituents also become unavailable. This train of events leads to phase-out risks for ongoing maintenance of Army legacy platforms. One way to reduce life-cycle expenses is to focus on the environmental sustainability of the adhesive and surface pretreatment during initial research and development.

Fig. 1 Notional life-cycle costs for a DOD weapon system


The surface pretreatments utilized for this research are commercially available and qualified, or in the process of being qualified, under Federal Specification TT-C-490F,2 as with Type II or IV hexavalent chromium-free chemical conversion coatings. A majority of TT-C-490F qualified pretreatments were originally formulated as zinc-based pretreatments to prevent corrosion on steel, not as bonding surface pretreatments. If these environmentally friendly TT-C-490F pretreatments prove compatible for adhesive bonding then they could potentially function simultaneously as both corrosion inhibitors and adhesion promoters.

SCIGRIP SG805, which is methacrylate based and marketed for high-temperature applications,3 was the adhesive examined for this study. This adhesive was tested against screening standards protocols outlined in ARL-ADHES-QA-001.00 rev 1.04 and for compatibility with the environmentally sustainable TT-C-490F Type IV surface pretreatments. Testing consisted of single-lap-joint shear tensile testing using 2024 T3 aluminum and 1010 mild steel specimens at room temperature (RT), after 14 d of hot/wet (H/W) immersion at 63 °C, and in-situ at an ET of 71 °C. Single-lap-joints are widely studied in the literature and allow for minimal labor intensive standardized testing.5 Adhesives that retain 75% of their dry maximum strength (Smax) after environmental conditioning and during in-situ ET testing are of interest. The methacrylate adhesive showed promising high-initial bond strength and H/W durability but was unable to meet ET performance retention requirements. The use of environmentally sustainable TT-C-490F pretreatments resulted in little to no loss of adhesive bond strength during H/W conditioning and their potential use as bonding promoters for adhesives is worthy of further investigation.

2. Experimental

2.1 Materials and Environmental Assessment

SCIGRIP SG805 methacrylate adhesive was used for bonding the single-lap-joints. The TT-C-490F surface pretreatments included Bonderite M-NT 7400 (Henkel Corporation), SurTec 650 (CST-Surtec, Inc.), and ZIRCOBOND 4200 (PPG Industries, Inc.). While qualified for TT-C-490F, Oxysilan 9810/2 (Chemetall US, Inc.) was not included due to sample nonavailability at the commencement of the study. Additional environmentally sustainable surface pretreatments, as claimed by the manufacturers, included Bonderite M-NT 5700 (Henkel Corporation), XBOND 4000DM-DR (PPG Industries, Inc.), and AC-131 BB (3M Company). Grit blasting and an academic 3-aminopropyltrimethoxysilane (APS) coupling agent were used as performance comparisons with the TT-C-490F qualified and other commercial pretreatments.


Appendix A lists associated environmental restrictions matched against the constitutive chemical components of the adhesive and surface pretreatments using the restricted substances database feature of the US Army Research Laboratory’s Materials Selection and Analysis Tool (MSAT) database.6 The restricted substances database references chemical abstract service numbers reported in the manufacturer’s safety data sheets against current and pending environmental legislation in North America, Europe, and Asia. The highest substance rating returned was “caution”. None of the constitutive chemical components of the adhesive and surface pretreatments used for this study were reported as being “banned” by any current or pending regulations.

2.2 Joint Geometry

The single-lap-joints were fabricated and tested using American Society for Testing and Materials (ASTM) D1002-10 as the basis standard, schematically represented in Fig. 2.7

Fig. 2 Illustration of the adhesively bonded single-lap-joint test specimen configuration (refer to ASTM D1002-10 for dimensions)

Maximum strength (Smax) is calculated by dividing the maximum load (Pmax) by the bonded area (A). The overlap length is 12.7 mm and the joint width is 25.4 mm.

APS max

max =

Area in Test Grips

Area in Test Grips Bonded Area

Bondline

Top-down view

Side view

Overflow fillet


Maximum strength and mode-of-failure represent the accepted standard reported outputs of single-lap-joint testing in both industry and academia.8

2.2.1 Surface Preparation

Preparation of the methacrylate adhesive bonded single-lap-joints followed procedures outlined in ARL-ADHES-QA-001.01 rev 2.2.9 The single-lap-joint substrates used 2024 T3 aluminum and 1010 steel coupons with an average thickness of approximately 1.60 and 1.52 mm, respectively. Sandpaper (180-grit aluminum oxide), an acetone wipe down, and an abrasive disc (3M Scotch-Brite Roloc, light grinding and blending disc, part number 60357) were used to initially remove oils and large deposits of oxide corrosion from the surfaces of the aluminum and steel. The coupons were then abrasive media blasted with clean and unused 60-grit aluminum oxide. From this point forward, the intended bonding surface of each coupon came into contact only with its corresponding coupon’s grit-blasted bonding surface or air. After being blown off with a thin stream of nitrogen gas, the various TT-C-490F pretreatments were applied in accordance with their manufacturer’s instructions. All of the pretreatments except for the APS and AC-131 BB sol-gel were applied by dip-coating the coupons for 2 min (Fig. 3), rinsed for 30 s with deionized water, and again blown off with a thin stream of nitrogen gas to produce a thin, uniform coating. The APS was also applied using the dip-coat technique; however, the coupons were blown off with nitrogen gas immediately after and then placed in an oven for 1 h at 65 °C. The AC-131 BB sol gel was brush applied to the surface intended for bonding, allowed to wet for 2 min, and then immediately blown off with nitrogen gas. All surface preparation was completed within 4 h of bonding.

Fig. 3 Single-lap-joint coupons undergoing dip-coat pretreatment


2.2.2 Bonding

The methacrylate adhesive has a set time of 5 min, so it was imperative that the assembly components of the bonding tooling fixture were gathered beforehand to facilitate a quick-bonding process, as shown in Fig. 4. Bondline thickness and overlap dimension control were essential to reducing possible sources of experimental error. Spacer shims (0.762 mm) were used to set the bondline thickness. The tooling fixture is also equipped with alignment pins to set orientation and overlap length.9

Fig. 4 Single-lap-joint bonding tooling fixture components

A pneumatic gun with a static-mixing head was used to dispense the 2-part adhesive with the required 10:1 ratio, per the manufacturer’s recommendations.10 The methacrylate adhesive was applied to an area slightly larger than the overlap area of 12.7 × 25.4 mm at the front of each finger on the coupon. Bonding pressure was maintained by placing weights on top of the assembled tooling fixture to ensure intimate contact with the bondline thickness spacer shims while the adhesive was curing. Figure 5 shows the tooling fixture assembly stacking sequence. The cure cycle was 4 d at room temperature. In addition, the methacrylate adhesive was also cast into silicone molds and allowed to cure, to yield thin-rectangular specimen bars for use in dynamic mechanical analysis (DMA) testing.


Fig. 5 Stacking assembly for fabrication of single-lap-joint panel

2.3 Testing

The MSAT database was used to collect the data following the workflow protocols outlined in ARL-TR-7696.11

2.3.1 Mechanical Testing

The test procedure for performing the breaking strengths of single-lap-joint samples was conducted in accordance to paragraphs 9.1 and 9.2 of ASTM D1002-10.7 instrumented mechanical testing frame with a 25-kN load cell was used to ensure


that the breaking load of single-lap-joint samples fell between 15% and 85% of the cell’s full-scale capacity. A crosshead speed of 1.27 mm/min was used with a pair of self-aligning grips that held the outer 25.4 mm of each end of the single-lap-joint test sample.

H/W-conditioned samples were fully immersed in deionized (DI) water for 14 d at 63 °C, prior to mechanical testing. Mechanical tests occurred on the same day as their removal from the heated bath. Once removed, samples were allowed to cool to RT and patted dry with paper towels prior to loading into the test frame. In-situ ET testing was conducted using a heated static oven that enclosed around the load frame, which was allowed to stabilize at a temperature of 71 °C, +/−3 °C for 45 min, prior to the start of mechanical testing. Before loading samples within the test grips, each single-lap-joint sample was allowed to rest at least 10 min at RT. Once placed within the grips, the thermocouple attached and the oven door closed and secured, the sample’s temperature was then monitored for 10 min with a digital thermometer until the sample reached equilibrium with the oven temperature and was stable. H/W and ET conditions, which were recommended per ARL-ADHES-QA-001.00 rev 1.0,4 were based on test method guidelines provided by Military Standard-810G (MIL-STD-810G), Environmental Engineering Considerations and Laboratory Tests.12,13

Upon completion of mechanical testing, failure surfaces of each broken single-lap-joint coupon sample were digitally imaged using a flatbed scanner (Hewlett-Packard OfficeJet D145) and archived in MSAT. Failed test coupons were then manually labeled with a MSAT identification (ID) code, and this information was then embedded within the image, preserving data integrity by eliminating file naming errors. Images were scanned at 300-dots per inch (dpi) resolution and saved as a tagged image file format (TIFF), which is a common minimum recommendation for photo archiving.14 After the fractured surfaces were visually inspected and examined, the tested coupons were assigned either an adhesive, cohesive, or mixed-mode (MM) type of failure designation. Load versus displacement plots and failure surface scans are provided in Appendix B.

2.3.2 Dynamic Mechanical Analysis The small bulk adhesive rectangular sample bars made during the bonding process were sanded to uniform thickness using 60 grit followed by 180-grit aluminum oxide sandpaper. Thickness for single-cantilever DMA testing of the cured adhesive was between 2 and 4 mm. The samples were cut to a length of approximately 35 mm using a water saw from sections that were free of visible voiding defects. The thickness and width of a sample was measured using a telescoping micrometer before tightening it in the DMA clamps with a torque of


0.79 N∙m. DMA was performed with a constant frequency of 1 Hz and a constant strain of 0.2%. The sample was equilibrated at 0 °C and held there for 10 min before being heated to 71 °C at a rate of 2 °C/min. Once this process was completed, the clamps were retightened, the length of the sample between the clamps was measured and recorded, and DMA was run a second time on the same sample. DMA testing yielded the storage modulus (E’), loss modulus (E’’), and loss tangent (tan δ) of the methacrylate adhesive, allowing for determination of the adhesive’s glass transition temperature (Tg).

3. Results

Sample sets were organized by substrate material, surface pretreatment, and conditioning method. Tables 1 and 2 provide a quantitative summary of tensile testing results along with associated modes of failure for the aluminum and steel single-lap-joints. Figures 6–9 show plots of maximum load and displacement at failure for the aluminum and steel joints. A load versus extension at complete failure plot is provided for each set, containing curves for all samples within that set. An example failure surface scan is included below each graph to show a representative sample for mode of failure confirmation. Complete records of test data and failure surface scans may be accessed at the National Institute of Standards and Technology Dspace repository site http://hdl.handle.net/11256/937. A summary of the data and supporting metadata descriptors are found in Appendix C.

Table 1 Aluminum 2024 T3, RT, H/W, and ET conditioning. Mode-of-failure: adhesive (ADH), cohesive (COH), and MM.

Surface pretreatment

RT conditioning H/W conditioning ET conditioning

Smax (MPa)

dfailure

(mm) Mode-of-

failure Smax

(MPa) dfailure

(mm) Mode-of-

failure Smax

(MPa) dfailure

(mm) Mode-of-

failure

Grit Blast 19.9 (+0.7)

1.59 (+0.16) MM 18.8

(+0.8) 1.74

(+0.18) MM 8.45 (+0.32)

2.40 (+0.35) MM

3-APS 11.2 (+1.1)

0.72 (+0.03) ADH 12.2

(+0.8) 1.01

(+0.08) ADH 5.66 (+0.46)

3.49 (+0.75) ADH

AC-131 20.6 (+0.2)

1.79 (+0.10) MM 19.4

(+0.3) 2.14

(+0.09) MM Not tested

Not tested NA

SurTec-650 20.0 (+0.2)

1.59 (+0.08) MM 19.3

(+0.6) 1.92


Not tested NA

SerTec-5700 17.5 (+0.4)

1.34 (+0.20) ADH/MM 19.6

(+0.1) 2.21

(+0.07) ADH/MM Not tested

Not tested NA

SerTec-7400 17.9 (+0.9)

1.48 (+0.32) ADH/MM 19.1

(+0.2) 1.95


Not tested NA

XBOND 20.1 (+0.8)

1.64 (+0.18) ADH/MM 19.4

(+0.4) 1.91


Not tested NA

ZIRCOBOND 20.7 (+0.5)

1.82 (+0.09) MM 19.5

(+0.7) 2.05


Not tested NA

NA = not applicable

http://hdl.handle.net/11256/937


Table 2 1010 mild steel, RT and H/W conditioning. ET conditioning not tested for steel samples. Mode-of-failure: ADH, COH, and MM.


RT conditioning H/W conditioning

Smax

(MPa) dfailure

(mm)

Mode-of-failure Smax

(MPa) dfailure

(mm)

Mode-of- failure

AC-131 17.8 (±0.5)

1.51 (±0.10) MM 18.7

(±0.4) 1.73

(+0.12) MM

SurTec-650 21.6 (±0.6)

1.95 (±0.08) MM 20.3

(±0.7) 2.02

(+0.14) MM

SerTec-5700 20.9 (±0.5)

2.11 (+0.11) MM 20.6

(±0.4) 2.02

(+0.08) MM

SerTec-7400 20.9 (±0.4)

1.94 (+0.06) MM 20.2

(±0.5) 1.98

(+0.05) MM

XBOND 21.2 (±0.8)

1.89 (+0.07) MM 20.5

(±0.3) 2.11

(+0.06) MM

ZIRCOBOND 20.6 (±0.5)

1.82 (+0.22) MM 19.4

(±0.6) 1.97

(+0.11) MM

Fig. 6 Average maximum strength at failure (MPa) for aluminum 2024 T3, RT, H/W, and ET conditioning

19.918.8

8.45

11.212.2

5.66

20.6

19.4

0

2019.3

0

17.5

19.6

0

17.9

19.1

0

20.119.4

0

20.7

19.5

00

5

10

15

20

25

Room Temperature (RT) Conditioning Hot/Wet (H/W) Conditioning Elevated Temperature (ET)Conditioning

Smax (MPa) 0 0

Aver

age

Max

imum

Str

engt

h at

Fai

lure

(MPa

)

Surface Pretreatment on Aluminium SubstrateGrit Blast 3-APS AC-131 SurTec-650 SerTec-5700 SerTec-7400 XBOND ZIRCOBOND


Fig. 7 Average maximum displacement at failure (mm) for aluminum 2024 T3, RT, H/W, and ET conditioning

Fig. 8 Average maximum strength at failure (MPa) for 1010 mild steel, RT, and H/W conditioning. ET conditioning not tested for steel samples.

1.591.74

2.4

0.72

1.01

3.49

1.79

2.14

1.59

1.92

1.34

2.21

1.48

1.95

1.64

1.911.82

2.05

0

0.25

0.5

0.75

1

1.25

1.5

1.75

2

2.25

2.5

2.75

3

3.25

3.5

3.75

Room Temperature (RT)Conditioning

Hot/Wet (H/W) Conditioning Elevated Temperature (ET)Conditioning

Aver

age

Max

imum

Dis

plac

emen

t at F

ailu

re (m

m)

Surface Pretreatment on Aluminium SubstrateGrit Blast 3-APS AC-131 SurTec-650 SerTec-5700 SerTec-7400 XBOND ZIRCOBOND

17.818.7

21.6

20.320.9 20.620.9

20.221.2

20.520.619.4

0

5

10

15

20

25

Room Temperature (RT) Conditioning Hot/Wet (H/W) Conditioning

Ave. Smax (MPa) 0Aver

age

Max

imum

Str

engt

h at

Fai

lure

(MPa

)

Surface Pretreatment on Steel Substrate

AC-131 SurTec-650 SurTec-5700 SurTec-7400 XBOND ZIRCOBOND


Fig. 9 Average maximum displacement at failure (mm) for 1010 mild steel, RT, and H/W conditioning. ET conditioning not tested for steel samples.

4. Discussion

The bonded single-lap-joints with the SG805 adhesive and sustainable TT-C-490F pretreatments yielded strengths of approximately 19 MPa. A majority of the aluminum lap joints, and all of the steel lap joints, had mixed-mode failure. At RT, the SG805 mechanical performance using the aluminum coupons with the grit-blasted surface preparation was comparable to the chemical pretreatments (Fig. 10), including similar failure modes as shown in Fig. 11. The grit-blasted samples also retained approximately 94% of their dry strength following H/W conditioning, as summarized in Table 3. The results for the grit-blasted samples are consistent with observations for methacrylate adhesive usage for dental applications, both with and without added silane coupling agent pretreatments, where good long-term wet durability is essential.15–17 Steel single-lap-joints with a grit-blast-only surface pretreatment were not tested.

1.51

1.73

1.95 2.022.11 2.021.94 1.98

1.89

2.11

1.821.97

0

0.25

0.5

0.75

1

1.25

1.5

1.75

2

2.25

2.5

2.75

3

3.25

3.5

3.75

Room Temperature (RT) Conditioning Hot/Wet (H/W) Conditioning

Ave. dfailure (mm)

Aver

age

Max

imum

Dis

plac

emen

t at F

ailu

re (m

m)

Surface Pretreatment on Steel SubstrateAC-131 SurTec-650 SurTec-5700 SurTec-7400 XBOND ZIRCOBOND


Fig. 10 Load vs. displacement response for aluminum single-lap-joints pretreated by grit blasting and with ZIRCOBOND TT-C-490F Type IV surface pretreatment

Fig. 11 Failure surfaces for aluminum single-lap-joint with grit-blasted surface (left) and ZIRCOBOND 4200 (right) pretreatments

0

1000

2000

3000

4000

5000

6000

7000

8000

0 0.5 1 1.5 2

Load

(N)

Displacement (mm)

Aluminum - ZIRCOBOND

Aluminum - Grit Blast

Aluminum pretreated with grit blast Aluminum pretreated with ZIRCOBOND 4200


The aluminum samples with the APS pretreatment had lower strengths and displacements to failure when compared with the TT-C-490F pretreatments as shown in Fig. 12. The amine functionality of the APS should be reactive toward the methacrylate groups of the adhesive through a Michael addition mechanism18 but was perhaps negated by the cure kinetics or other additives present in the adhesive, as seen by the adhesive mode-of-failure in Fig. 13. Methacrylate functional silane coupling agents have been shown to enhance adhesion with methacrylate-based adhesives and may show higher strengths with SG805.19

The steel single-lap-joints samples pretreated with AC-131 showed visual flash corrosion during its application. This phenomenon was not observed in any of the other pretreatments, and the corresponding load versus displacement response shown in Fig. 12 depicts lower peak properties than the TT-C-490F Type IV qualified pretreatments. The AC-131 pretreatment is a water-based system and was applied via brush wetting rather than the dip-coating technique used for the other chemical pretreatments. The brush-wetting method allows for air exposure and provides the corrosive environment necessary for an oxide layer to form. The failure surfaces of the steel joints treated with AC-131 showed adhesive mode-of-failure with evidence of the flash corrosion seen on the adhesive and steel adherend. The AC-131 provided comparable strengths when applied to the aluminum joints, as summarized in Table 1.

Fig. 12 Load vs. displacement response for aluminum single-lap-joints pretreated with APS, steel samples pretreated with AC-131, and steel and aluminum pretreated with ZIRCOBOND TT-C-490F Type IV surface pretreatment

0

1000

2000

3000

4000

5000

6000

7000

0 0.5 1 1.5 2

Load

(N)

Displacement (mm)

Aluminum - ZIRCOBOND

Steel - ZIRCOBOND

Steel - AC-131 BB

Aluminum - APS


Fig. 13 Failure surfaces for aluminum single-lap-joint pretreated with APS (left) and steel pretreated with AC-131 (right)

Comparison within the aluminum and steel adherends shows similar, if not increased, performance of the SG805 methacrylate adhesive after H/W conditioning, as summarized in Table 3. The adhesive was likely undergoing additional postcure at the 63 °C temperature of the H/W conditioning, which can lead to an increase in strength. For an adhesive systems to pass the screening testing, it is required to retain 75% of its RT strength after H/W conditioning, which the SG805 methacrylate adhesive achieved.

Aluminum pretreated with APS Steel pretreated with AC-131


Table 3 Average property changes after H/W and ET conditioning


2024 T3 Aluminum 1010 mild steel

Average strength (Smax) retention after

conditioning (%)

Average displacement (dfailure) change after

conditioning (%)

Average strength (Smax) retention

after conditioning (%)

Average displacement

(dfailure) change after conditioning

(%) H/W

conditioning (ET)

conditioning H/W

conditioning (ET)

conditioning H/W conditioning

Grit Blast 94 42 9 51 NA NA 3-APS 109 51 39 385 NA NA AC-131 106 NA 20 NA 105 15 SurTec-650 104 NA 21 NA 106 4 SerTec-5700 112 NA 65 NA 101 4 SerTec-7400 107 NA 32 NA 103 2 XBOND 103 NA 16 NA 103 12 ZIRCOBOND 106 NA 13 NA 106 8

Elevated temperature testing showed a significant decrease in bond performance, as shown in Fig. 14. The grit blasted single-lap-joint strength decreased from 19.9 MPa at RT to 8.45 MPa at 71 °C, for only a 42% retention in strength. Elevated temperature performance in the absence of moisture exposure is unlikely to degrade due to the surface pretreatment and is more reliant on the bulk adhesive properties. Although the lap joints pretreated with 3-APS displayed a high-average extension to failure of 3.49 mm, this was largely due to tensile failure of the adhesive after it had de-bonded from the substrate (Fig. 15). Elevated temperature testing was conducted at 71 °C, which is within the glass transition region of this adhesive, as shown in the storage and loss modulus DMA plot in Fig. 16. As the adhesive moves from the glassy to rubbery state, it becomes more ductile and is unable to sustain the high loads that are possible at lower temperatures.


Fig. 14 Load vs. displacement response for grit-blasted aluminum single-lap-joints tested at RT and 71 °C

Fig. 15 Failure surfaces for grit-blasted aluminum single-lap-joints tested at RT (left) and 71°C (right)

0

1000

2000

3000

4000

5000

6000

7000

8000

0 0.5 1 1.5 2 2.5 3

Load

(N)

Displacement (mm)

RT

71 °C

Aluminum pretreated with grit blast - RT Aluminum pretreated with grit blast – 71 °C


Fig. 16 Storage modulus (E’) and loss modulus (E’’) vs. temperature for SG805

5. Conclusions

SG805 was tested against ARL-ADHES-QA-001.00 rev 1.0 and for compatibility with the environmentally sustainable TT-C-490F surface pretreatments. Testing consisted of single-lap-joint shear tensile testing using aluminum and steel specimens with RT, H/W, and ET conditioning. The SG805 methacrylate adhesive was found to be suitable for RT and H/W conditions but showed excessive loss of strength at ET. At RT and after H/W conditioning the adhesive performed well on both aluminum and steel substrates, even when no chemical surface pretreatment was applied. Environmentally sustainable TT-C-490F Type IV inorganic pretreatments resulted in little to no loss of adhesive bond strength during H/W conditioning and their potential use as bonding pretreatments is worthy of further investigation. The TT-C-490F pretreatments offer the advantage of corrosion protection, which should be considered for bonding applications. Further research with the SG805 methacrylate adhesive is warranted for applications with lower service temperature requirements.

0

20

40

60

80

100

120

140

00.20.40.60.8

11.21.41.61.8

2

0 25 50 75 100 125 150

E'' (

MPa

)

E' (G

Pa)

Temperature (°C)


6. References

1. Jones G, White E, Ryan E, Ritschel J. Investigation into the ratio of operating and support costs to life-cycle costs for DOD weapon systems. Defense Acquisition Research Journal. 2014;21(1):442–464.

2. Federal specification TT-C-490F w/amendment 3. Chemical conversion coatings and pretreatments for metallic substrates (base for organic coatings). Aberdeen Proving Ground (MD): Army Research Laboratory (US); 2016 Feb 29.

3. SCIGRIP launches new MMA adhesive with increased thermal resistance. Cincinnati (OH): CompositesWorld; c2017 [accessed 2016 Sep 9]. http://www.compositesworld.com/products/scigrip-launches-new-mma -adhesive-with-increased-thermal-resistance.

4. Jensen R, DeSchepper D, Flanagan D, Kosik-Chaney W, Robinette J, Chaney G, Pergantis C. Adhesives: test method, group assignment, and categorization guide for high-loading-rate applications. Aberdeen Proving Ground (MD): Army Research Laboratory (US); 2014 Jun. Report No.: ARL-SR-288.

5. da Silva LFM, Carbas RJC, Critchlow GW, Figueiredo MAV, Brown K. Effect of material, geometry, surface treatment and environment on the shear strength of single lap joints. International Journal of Adhesion and Adhesives. 2009;(29):621–632.

6. MSAT uses GRANTA MI as the base software operating package. Available: www.grantadesign.com/products/mi/. ARL’s MSAT database is housed and supported by NASA Marshall Space Flight Center, Huntsville, AL.

7. ASTM D1002-10. Standard test method for apparent shear strength of single-lap-joint adhesively bonded metal specimens by tension loading (metal-to-metal). West Conshohocken (PA): ASTM International; 2010. DOI: 10.1520/D1002-10, www.astm.org.

8. Alia C, Jofre-Reche JA, Suarez JC, Arenas JM, Martin-Martinez JM. Influence of post-curing temperature on the structure, properties, and adhesion of vinyl ester adhesive. Journal of Adhesion Science and Technology. 2015;(29):518–531.


9. Jensen R, DeSchepper D, Flanagan D, Chaney G, Pergantis C. Adhesives: test method, group assignment, and categorization guide for high-loading-rate applications – preparation and testing of single lap joints. ARL-ADHES-QA-001.00 rev 2.2. Aberdeen Proving Ground (MD): Army Research Laboratory (US); 2016 Apr. Report No.: ARL-SR-0356.

10. Technical data sheet, SG800 methacrylate adhesives, SCIGRIP Americas. [accessed 2015 Feb]. http://www.scigrip.com/product.php?id=150.

11. Jensen R, DeSchepper D, Flanagan D. Multivariate analysis of high through-put adhesively bonded single lap joints: experimental and workflow protocols. Aberdeen Proving Ground (MD): Army Research Laboratory (US); 2016 June. Report No.: ARL-TR-7696.

12. MIL-STD-810G. Department of Defense test method standard, environmental engineering considerations and laboratory tests. Laboratory test method 507.5, humidity. Aberdeen Proving Ground, (MD): Army Developmental Test Command (US); 2008 Oct 31.

13. MIL-STD-810G. Department of Defense test method standard, environmental engineering considerations and laboratory tests. Laboratory test method 501.5, high temperature. Aberdeen Proving Ground, (MD): Army Developmental Test Command (US); 2008 Oct 31.

14. Digital imaging standards. Hartford (CT): Office of the Public Records Administrator, Connecticut State Library; 2014.

15. Valente LL, Sarkis-Onofre R, Gonçalves AP, Fernández E, Loomans B, Moraes RR. Repair bond strength of dental composites: systematic review and meta-analysis. International Journal of Adhesion & Adhesives. 2016;(69):15–26.

16. Mustafa AA, Matinlinna JP, Saidin S, Abdul Kadir MR. The influence of experimental silane primers on dentin bond strength and morphology: A laboratory and finite element analysis study. The Journal of Prosthetic Dentistry. 2014;(112):1498–1506.

17. Song L, Ye Q, Ge X, Misra A, Spencer P. Mimicking nature: Self-strengthening properties in a dental adhesive. Acta Biomaterialia. 2016;(35): 138–152.

18. Mather B, Viswanathan K, Miller K, Long T. Michael addition reactions in macromolecular design for emerging technologies. Progress in Polymer Science. 2006;(31):487–531.


19. Ginzburg-Turgeman R, Guion JP, Mandler D. Improving the adhesion of polymethacrylate thin films onto indium tin oxide electrodes using a silane-based, molecular adhesive. Journal of Solid State Electrochemistry. 2011;15: 2401–2407.


Appendix A. Environmental Restrictions Listed against the Adhesive and Surface Pretreatments

22

US Environmental Protection Agency (EPA)

Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) hazardous substances

NA

US EPA Emergency Planning and Community Right-to-Know Act (EPCRA) Section 314, Toxic Chemicals

NA

US EPA EPA's List of Lists (LoL) NA

US EPANational Emission Standards for Hazardous Air Pollutants (NESHAP) for Stationary Reciprocating Internal Combustion Engines-US Air Toxics Regulations

NA

AeroSpace and Defence Industries Association of

Europe - (ASD)ASD-Standardization Declarable Substances List Caution

US EPAEPCRA-Section 304, Extremely Hazardous Substances, Reportable Quality (RQ)

NA

European Trade Union Confederation (ETUC)

ETUC Priority List Caution

European Chemical Agency (ECHA)

Community Rolling Action Plan (CoRAP) List Caution

Bonderite M-NT 7400

•TT-C-490F•TYPE IV, CLASS A, DEGREASE AND ABRASIVE BLAST and TYPE IV, CLASS B AND CLASS C

SurTec 650 ChromitAL•TT-C-490F•TYPE IV, CLASS A, DEGREASE AND ABRASIVE BLAST

ZIRCOBOND 4200DM-DR

•TT-C-490F•TYPE IV, CLASS A, DEGREASE AND ABRASIVE BLAST and TYPE IV, CLASS B AND CLASS C

Bonderite M-NT 5700

XBOND 4000DM-DR

Legislation Rating

SG805 Adhesive

Legistrative Organization

US EPA

US EPA

Adhesive or Surface Pretreatment

Substance Name

CAS Number

Substance Rating

Legislation Name

Methyl Methacrylate

80-62-6 Caution

Phosphoric Acid

7664-38-2 Caution CERCLA hazardous substances NA

Zirconium Potassium Fluoride

16923-95-8 Caution CERCLA hazardous substances NA

Cupric Nitrate 3251-23-8 Caution

No hazardous substance ratings associated with CAS numbers provided in manufacturer's safety data sheet.

CERCLA hazardous substances NA

No hazardous ingredients claimed in manufacturer's safety data sheet.

US EPA


23

US EPA CERCLA hazardous substances NAUS EPA EPA's List of Lists (LoL) NA

ASD ASD-STAN Declarable Substances List CautionUS EPA EPCRA Section 304, Extremely Hazardous Substances, RQ NAUS EPA CERCLA hazardous substances NAUS EPA EPCRA Section 313, Toxic Chemicals NAUS EPA The EPA's List of Lists (LoL) NA

NESHAP-US Air Toxics Regulations NA

US EPA NESHAP for Stationary Reciprocating Internal Combustion Engines

NA

ASD ASD-STAN Declarable Substances List Caution

European Union (EU) Directive 1996/82/EC (Seveso II) on the control of major-accident hazards involving dangerous substances

NA

US EPA EPCRA Section 304, Extremely Hazardous Substances, RQ NA

EU Global Automotive Declarable Substance List (GADSL) CautionETUC ETUC Priority List CautionECHA Community Rolling Action Plan (CoRAP) List Caution

APS

Aluminum Oxide Grit Blast

OXSILAN 9810/2 US EPA CERCLA hazardous substances NA

•TT-C-490FUS Department of

Homeland Security (DHS)Chemicals of Concern (CoC) NA

US EPAEPCRA Section 304, Extremely Hazardous Substances, Reportable Quality (RQ)

NA

US EPA EPCRA Section 313, Toxic Chemicals NA

US EPAClean Air Act Section 112(R): Accidental Release Prevention/Risk Management Plan Rule

NA

US EPA EPA's List of Lists (LoL) NAASD ASD-STAN Declarable Substances List Caution

US EPAEPCRA Section 302, Extremely Hazardous Substances, Threshold Planning Quantity (TPQ)

NA

Legislation Rating

Legistrative Organization

Adhesive or Surface Pretreatment

Substance Name

CAS Number

Substance Rating

Legislation Name

AC-131 BB Methanol 67-56-1 Caution

AC-131 BB Acetic Acid 64-19-7 Caution

•TYPE IV, CLASS A, DEGREASE AND ABRASIVE BLAST and TYPE IV, CLASS B AND CLASS C

No hazardous substance ratings associated with CAS numbers provided in manufacturer's safety data sheet.

CAS number 1344-24-1 list as “Caution” for fibrous forms only.

Nitric Acid 7697-37-2 Caution



INTENTIONALLY LEFT BLANK.


Appendix B. Load versus Displacement Curves and Failure Surface Scans


Complete records of test data and failure surface scans may be accessed at the National Institute of Standards and Technology Dspace repository site http://hdl.handle.net/11256/937.

B.1 Substrate = 2024 T3 Aluminum, Sample Conditioning = Room Temperature (RT)

Fig. B-1 Load vs. extension (displacement) for single-lap-joints with aluminum oxide grit blast surface pretreatment. Materials Selection and Analysis Tool (MSAT) identifications (IDs) = 20150215–20150219, substrate = 2024 T3 aluminum, sample conditioning = RT.

Fig. B-2 Failure surfaces for single-lap-joint with aluminum oxide grit blast surface pretreatment. MSAT ID = 20150215, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = mixed-mode (MM).


Fig. B-3 Load vs. extension (displacement) for single-lap-joints with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT IDs = 20150225–20150229, substrate = 2024 T3 aluminum, and sample conditioning = RT.

Fig. B-4 Failure surfaces for single-lap-joint with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT ID = 20150225, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive.


Fig. B-5 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150235–20150239, substrate = 2024 T3 aluminum, and sample conditioning = RT.

Fig. B-6 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150235, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = MM.


Fig. B-7 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150245–20150249, substrate = 2024 T3 aluminum, and sample conditioning = RT.

Fig. B-8 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150245, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = MM.


Fig. B-9 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150255–20150259, substrate = 2024 T3 aluminum, and sample conditioning = RT.

Fig. B-10 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150255, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive/ MM.


Fig. B-11 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150265–20150269, substrate = 2024 T3 aluminum, and sample conditioning = RT.

Fig. B-12 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150265, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive/ MM.


Fig. B-13 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150275–20150279, substrate = 2024 T3 aluminum, and sample conditioning = RT.

Fig. B-14 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150275, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = adhesive/ MM.


Fig. B-15 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150285–20150289, substrate = 2024 T3 aluminum, and sample conditioning = RT.

Fig. B-16 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150285, substrate = 2024 T3 aluminum, and sample conditioning = RT. Mode-of-failure = MM.


B.2 Substrate = 2024 T3 Aluminum, Sample Conditioning = Hot/Wet (H/W)

Fig. B-17 Load vs. extension (displacement) for single-lap-joints with aluminum oxide grit blast surface pretreatment. MSAT IDs = 20150220–20150224, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-18 Failure surfaces for single-lap-joint with aluminum oxide grit blast surface pretreatment. MSAT ID = 20150222, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-19 Load vs. extension (displacement) for single-lap-joints with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT IDs = 20150230–20150234, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-20 Failure surfaces for single-lap-joint with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT ID = 20150230, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive.


Fig. B-21 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150240–20150244, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-22 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150240, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-23 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150250–20150254, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-24 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150250, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-25 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150260–20150264, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-26 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150260, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive/ MM.


Fig. B-27 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150270–20150274, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-28 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150270, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive/ MM.


Fig. B-29 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150280–20150284, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-30 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150280, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = adhesive/ MM.


Fig. B-31 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150290–20150294, substrate = 2024 T3 aluminum, and sample conditioning = H/W.

Fig. B-32 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150290, substrate = 2024 T3 aluminum, and sample conditioning = H/W. Mode-of-failure = MM.


B.3 Substrate = 2024 T3 Aluminum, Test Conditions = Elevated Temperature (ET)

Fig. B-33 Load vs. extension (displacement) for single-lap-joints with aluminum oxide grit blast surface pretreatment. MSAT IDs = 20150871–20150875, substrate = 2024 T3 aluminum, and test conditions = ET.

Fig. B-34 Failure surfaces for single-lap-joint with aluminum oxide grit blast surface pretreatment. MSAT ID = 20150871, substrate = 2024 T3 aluminum, and test conditions = ET. Mode-of-failure = MM.

-500

0

500

1000

1500

2000

2500

3000

-1 -0.5 0 0.5 1 1.5 2 2.5 3

Load

(N)

Extension (mm)


Fig. B-35 Load vs. extension (displacement) for single-lap-joints with 3-aminopropyltrimethoxysilane surface pretreatment. MSAT IDs = 20150388–20150392, substrate = 2024 T3 aluminum, and test conditions = ET.

Fig. B-36 Failure surfaces for single-lap-joint with 3-aminopropyltrimethoxysilane pretreatment. MSAT ID = 20150388, substrate = 2024 T3 aluminum, and test conditions = ET Mode-of-failure = adhesive.

-500

0

500

1000

1500

2000

2500

-1 0 1 2 3 4 5

Load

(N)

Extension (mm)


B.4 Substrate = 1010 Steel, Sample Conditioning = RT

Fig. B-37 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150438–20150442, substrate = 1010 steel, and sample conditioning = RT.

Fig. B-38 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150438, substrate = 1010 steel, sample conditioning = RT. Mode-of-failure = MM.


Fig. B-39 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150448–20150452, substrate = 1010 steel, and sample conditioning = RT.

Fig. B-40 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150448, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM.


Fig. B-41 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150458–20150462, substrate = 1010 steel, sample conditioning = RT.

Fig. B-42 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150461, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM.


Fig. B-43 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150468–20150472, substrate = 1010 steel, and sample conditioning = RT.

Fig. B-44 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150468, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM.


Fig. B-45 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150478–20150482, substrate = 1010 steel, and sample conditioning = RT.

Fig. B-46 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150478, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM.


Fig. B-47 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150488–20150492, substrate = 1010 steel, and sample conditioning = RT.

Fig. B-48 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150492, substrate = 1010 steel, and sample conditioning = RT. Mode-of-failure = MM.


B.5 Substrate = 1010 Steel, Sample Conditioning = H/W

Fig. B-49 Load vs. extension (displacement) for single-lap-joints with AC-131 BB surface pretreatment. MSAT IDs = 20150443–20150447, substrate = 1010 steel, and sample conditioning = H/W.

Fig. B-50 Failure surfaces for single-lap-joint with AC-131 BB surface pretreatment. MSAT ID = 20150443, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-51 Load vs. extension (displacement) for single-lap-joints with SurTec 650 surface pretreatment. MSAT IDs = 20150453–20150457, substrate = 1010 steel, and sample conditioning = H/W.

Fig. B-52 Failure surfaces for single-lap-joint with SurTec 650 surface pretreatment. MSAT ID = 20150453, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-53 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 5700 surface pretreatment. MSAT IDs = 20150463–20150467, substrate = 1010 steel, and sample conditioning = H/W.

Fig. B-54 Failure surfaces for single-lap-joint with Bonderite M-NT 5700 surface pretreatment. MSAT ID = 20150464, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-55 Load vs. extension (displacement) for single-lap-joints with Bonderite M-NT 7400 surface pretreatment. MSAT IDs = 20150473–20150477, substrate = 1010 steel, and sample conditioning = H/W.

Fig. B-56 Failure surfaces for single-lap-joint with Bonderite M-NT 7400 surface pretreatment. MSAT ID = 20150473, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-57 Load vs. extension (displacement) for single-lap-joints with XBOND 4000DM-DR surface pretreatment. MSAT IDs = 20150483–20150487, substrate = 1010 steel, and sample conditioning = H/W.

Fig. B-58 Failure surfaces for single-lap-joint with XBOND 4000DM-DR surface pretreatment. MSAT ID = 20150485, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM.


Fig. B-59 Load vs. extension (displacement) for single-lap-joints with ZIRCOBOND 4200 surface pretreatment. MSAT IDs = 20150493–20150497, substrate = 1010 steel, and sample conditioning = H/W.

Fig. B-60 Failure surfaces for single-lap-joint with ZIRCOBOND 4200 surface pretreatment. MSAT ID = 20150496, substrate = 1010 steel, and sample conditioning = H/W. Mode-of-failure = MM.


Appendix C. Supporting Digital File Archive Index


Table C-1 provides the reader with a reference list and URL (uniform resource locator) links to experimental data and supporting metadata descriptors archived in the National Institute of Standards and Technology (NIST) DSpace repository http://hdl.handle.net/11256/937.

Table C-1 Supporting data collection

File namea Description

Aluminum joints

Size: 301.1 MB Format: MS Excel, TIFF, PDF

Lab notes, load versus displacement data, and failure surface images

Steel joints

Size: 206.9 MB Format: MS Excel, TIFF, PDF

Lab notes, load versus displacement data, and failure surface images

DMA

Size: 2.213 MB Format: MS Excel and csv text

Dynamic mechanical analysis storage and loss modulus

Technical data sheets Size: 5.910 MB

Format: PDF Manufacturer technical and safety data sheets

Restricted substances Size: 22.38 KB

Format: MS Excel Currents and pending environmental legislations

Calibration certs Size: 9.393 MB

Format: PDF Calibration certificates for test equipment used

aAbbreviated file name as it appears on NIST site.

http://hdl.handle.net/11256/937


List of Symbols, Abbreviations, and Acronyms

A bonded area

ADH adhesive mode-of-failure

APS 3-aminopropyltrimethoxysilane

ASTM American Society for Testing and Materials

COH cohesive mode-of-failure

cond. conditioning

csv comma-separated values

DMA dynamic mechanical analysis

DOD Department of Defense

dpi dots per inch

E’ storage modulus

E’’ loss modulus

ET elevated temperature

ID sample identification number

min minute

mm millimeter

MM mixed-mode mode-of-failure

MPa megapascal

MS Microsoft

MSAT Materials Selection and Analysis Too

NIST National Institute of Standards and Technology

Pmax maximum load

PDF portable document format

RT room temperature

Smax maximum strength


Tg glass transition temperature

tan δ loss tangent

TIFF tagged image file format

txt text file format

URL uniform resource locator

ZIP archive file format


1 DEFENSE TECHNICAL (PDF) INFORMATION CTR DTIC OCA 2 DIRECTOR (PDF) US ARMY RESEARCH LAB RDRL CIO L IMAL HRA MAIL & RECORDS MGMT 1 GOVT PRINTG OFC (PDF) A MALHOTRA 4 DIR USARL (PDF) RDRL WMM C D DESCHEPPER D FLANAGAN R JENSEN J SNYDER

initial screening of environmentally sustainable surface ... screening of environmentally...

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